Preliminary work from our laboratory indicates that wounds in the sex skin of nonhuman primates heal more rapidly than those in other areas of skin. This accelerated healing capacity is probably related to the remarkable sensitivity of this specialized skin to steroid hormones. Although it is known that estrogens stimulate and progestins inhibit the swelling of this skin, it is not known whether such hormone treatments would influence the rate of wound healing, nor, if so, how such effects might be mediated. Consequently, we plan to first explore the precise effects of such hormones on normal sex skin by treating spayed pig-tailed macaques with various estradiol-progesterone regimens, and by sampling their sex skin at intervals. Sex skin specimens will be shared by several investigators and examined in three ways: with morphological techniques (electron microscopy, autoradiography and fluorescence microscopy), with steroid receptor assays, and with biosynthetic capacity assays (collagen and hyaluronic acid synthesis). We will then document with the same techniques how the rate and character of wound healing in sex skin varies during different hormonal states, and how changes in biosynthetic capacity and steroid receptor levels are correlated in healing sex skin. The information gathered from these studies will help us understand both the hormonal regulation of normal sex skin and the role of hormones in the rapid repair that occurs in sex skin. This research is relevant to a number of skin diseases, especially those that involve disordered fibroblast expression and to an understanding of the factors regulating wound healing in normal human skin.